Test phantom for X-ray imaging

1. A test phantom set for X-ray imaging, which comprises:

a circular hollow groove provided for penetrating through a slot body, and

a plurality of test phantoms configured to a periphery of the slot body,

wherein the plurality of test phantoms further comprise:

a phantom fin, having a plurality of circular grooves and a plurality of line pairs;

an edge plate configured to one side of the phantom fin, and

a phantom configured to be placed in the circular hollow groove.

2. The test phantom set defined in claim 1 , wherein the circular grooves have diameters of 0.5 mm˜4 mm.

3. The test phantom set defined in claim 1 , wherein the line pairs have widths of 1 line pairs per mm (1 p/mm)˜10 line pairs per mm (1 p/mm).

4. The test phantom set defined in claim 1 , comprising a plurality of phantom fins, wherein each of the phantom fins has different thickness.

5. The test phantom set defined in claim 1 , wherein the phantom fin has a thickness of 0.16 mm˜4.63 mm.

6. The test phantom set defined in claim 1 , wherein the phantom fin and the edge plate are made of tungsten, aluminum or PMMA.

7. The test phantom set defined in claim 1 ,

wherein each of test phantoms has a plurality of phantom fins and an edge plate;

wherein each of the edge plates is configured to have a shape enabling an identification of a direction by different areas of the edge plates provided for para-positional angle of the test phantom set.

8. The test phantom set defined in claim 7 , comprising: a stellated phantom being placed in the circular hollow groove; wherein the test phantoms are attached to the periphery of the slot body.

9. The test phantom set defined in claim 8 , wherein the circular hollow groove has a diameter of 50 mm to 55 mm.

10. The test phantom set defined in claim 8 , wherein the slot body is made of tungsten, aluminum or PMMA.

11. A measurement method for the focal spot of a test phantom for X-ray imaging, comprising:

(a) providing an X-ray imaging device comprising an X-ray source and an image detector;

(b) placing a test phantom set defined in claim 8 between the X-ray source and the image detector, wherein a distance ratio of a distance from the X-ray source to the image detector to-a distance from the X-ray source to the test phantom set is 1 to 3;

(c) irradiating X-rays from the X-ray source passing through a stellated phantom of the test phantom set, then received by the image detector to record and obtain an image;

(d) from the image, selecting one region with a limitation distinguishing degree or a limitation contrast ratio of the stellated phantom; and

(e) calculating the diameter and angle value of the region and the distance ratio to obtain a focal spot size or a focal spot value.

12. A measurement method for the parameters of a test phantom for X-ray imaging, comprising:

(a) providing an X-ray imaging device comprising an X-ray source and an image detector;

(b) placing a test phantom set defined in claim 7 in a front side of the image detector;

(c) irradiating X-rays from the X-ray source passing through the test phantom set, then received by the image detector to record and obtain an image;

(d) from the image, selecting one round slot with a limitation distinguishing degree or one line pair with a limitation contrast ratio of the test phantom set; and

(e) taking a value corresponding to the round slot or the line pair as a maximum resolution of the X-ray imaging device.

13. The method defined in claim 12 , further comprising:

(f) from the image, selecting one edge plate of the test phantom set to obtain an edge spread function (ESF); and

(g) calculating the differential of the ESF to obtain a line spread function.

14. The method defined in claim 13 , further comprising:

(h) calculating a Fourier transformation of the line spread function to obtain a modulation transfer function (MTF).

15. The method defined in claim 14 , further comprising:

(i) calculating the MTF based on a standard criterion to obtain an input power (W in ) and an output power (W out ) of the image detector; and

(g) calculating the MTF, output power and input power to obtain a detective quantum efficiency.